Análise das características fisiográficas e do tempo de concentração da bacia do Carão, Ceará

Abstract

The morphometry of a river basin provides a quantitative description of the drainage system and has great relevance in predicting the degree of vulnerability of the basin. River basin delineation was performed using Arc-GIS 10.2.2 software, based on the digital elevation model derived from the SRTM image of the ASTER satellite. Based on the found form factor of 0.12 and on the result of the compactness coefficient that was 1.64, it can be inferred that the Carão Basin is little susceptible to flooding under normal precipitation conditions. This finding is also validated by the low circularity index found in the study (0.36). The Carão Basin presented an average slope of 19.51% and main river length was 50.88 km. The concentration time obtained by the Kirpich methodology was 464 minutes, using the Temez formula, the result was 757 minutes; And by the formula of Ven te Chow the concentration time was 252 minutes. Therefore, it is concluded that the Carão basin has desirable physical characteristics, as well as vulnerability to floods, as well as an adequate concentration time when compared to other semi-arid rural basins.